#include <stdio.h>
struct Astruct
{
    char a;
    char b;
    int c;
} __attribute__((packed));

int main()
{
    printf("the size of int is : %d\n", (int)(sizeof(int)));
    printf("the size of Astruct is : %d\n", (int)(sizeof(struct Astruct)));
    return 0;
}